package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否完成登录过滤器
 */
@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*") // 需要在启动类添加扫描过滤器
@Slf4j
public class LoginCheckFilter implements Filter {
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

//        filterChain.doFilter(servletRequest, servletResponse);

        //1、获取本次请求的URI
        String uri = request.getRequestURI();
        String method = request.getMethod();
        log.info("拦截到了请求:{} 请求方式:{}",uri,method);
        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/login",
                "/user/sendMsg"
        };
        //2、判断本次请求是否需要处理
        boolean checked = check(urls, uri);
        //3、如果不需要处理，则直接放行
        if (checked) {
//            log.info("本次请求{}不需要处理", uri);
            filterChain.doFilter(servletRequest, servletResponse);
            return;
        }
        //4.1、判断登录状态，如果已登录，则直接放行
        if (request.getSession().getAttribute("employee") != null) {
//            log.info("用户已登录，用户ID是{}", request.getSession().getAttribute("employee"));

            // 赋值到线程对象，可以在线程任意地方调用里面参数
            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(servletRequest, servletResponse);
            return;
        }
        //4.2、判断登录状态，如果已登录，则直接放行
        if (request.getSession().getAttribute("user") != null) {
//            log.info("用户已登录，用户ID是{}", request.getSession().getAttribute("employee"));

            // 赋值到线程对象，可以在线程任意地方调用里面参数
            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(servletRequest, servletResponse);
            return;
        }
//        log.info("用户未登录");
        response.setContentType("text/html;charset=UTF-8"); // 解决中文变成？？？
        //5、如果未登录则返回未登录结果，通过输出流方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("未登录"))); // 向页面返回数据
    }

    /**
     * 判断路径是否放行
     *
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls, String requestURI) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match) {
                return true;
            }
        }
        return false;
    }
}
